Improve guard so it works for no eof new line

ftplugin/racket.vim

@@ -1,4 +1,5 @@
 if !exists('g:polyglot_disabled') || index(g:polyglot_disabled, 'racket') == -1
+
 " Language:     Racket
 " Maintainer:   Will Langstroth <will@langstroth.com>
 " URL:          http://github.com/wlangstroth/vim-racket
@@ -58,4 +59,5 @@ nnoremap <buffer> <f9> :!racket -t %<cr>
 
 "setl commentstring=;;%s
 setl commentstring=#\|\ %s\ \|#
+
 endif